I have an Intel i5-4210U running at 2.4 GHz, and Intel HD Graphics 4400 GPU.
My settings are just the default settings with DirectX11 (Hardware). (Software mode causes slowdown.)
I have tried disabling speedhacks but that just makes the rest of the game slow.

The game is GPU heavy as hell. Your processor is a 920 too, which is a REALLY good processor compared to his. It's not insanely slower than mine.

I mean I get like 99% GPU usage in the game, so onboard won't work, simply.

his processor has more STP then mine by like 200 so his cpu is not the issue ( then again blyss amd has 300+ stp over my cpu too yet same scene blyss struggles with my system run 60fps), not sure how u have 99% gpu usage less you using some insane multiplier like 6x cause my gpu barely touched usage wise.